Evaporation rates of alkanes and alkanols from acoustically levitated drops

Abstract

Evaporation constants of acoustically levitated drops from the homologue series of n-alkanes and 1-alkanols in ambient air have been evaluated by size and temperature measurements. The size of the pure liquid drops, within a diameter range of 0.1 to 2.5 mm, was monitored using a CCD camera, while temperature measurements were carried out by IR thermography. During drop evaporation, water from a humid environment with a relative humidity between 5 and 80% was condensed on the drop surface and in the case of n-pentane, the condensed water froze as a result of the evaporative cooling.

Acoustophoretic contactless transport and handling of matter in air

“…First, if the particle is large enough, it acts as a sponge, absorbing the liquid (Movie S9). With an evaporation rate of 0.0036 mm 2 /s for water (27), the droplet volume reduction due to evaporation (1.1% over 10 s) does not play a significant role. Alternatively, small porous particles (e.g., instant coffee granule) dissolve in the water droplet ( Fig.…”

“…This extends the capability of the present concept beyond the handling of spherical or nearspherical particle and droplet transport and to the controlled motion of very elongated, wire-like objects. As a result, an extremely elongated object with a characteristic length L much larger than λ can be levitated, propelled, transported, and rotated in a controllable manner, going beyond the widely accepted limit (9,11,14,15,27) of λ/2 for the maximum size of an acoustically levitated sample (Fig. 4 and Movie S11).…”

Differential and Variational Formalism for an Acoustically Levitating Drop

“…According to Theorem 1, finding the solution of (1)-(4) (nondimensional statement (8)) is equivalent to description of the extremal points of the action (24). Adopting the nondimensional variational statement, substituting (19) into variational and differential formulations of Theorem 1 and choosing…”

“…The technology facilitates preventing the liquid contamination and intensifying the chemical reactions. The acoustic levitators are also used in physical measurements of the surface tension and the liquid viscosity [6,7,8]. A typical design of an acoustic levitator is schematically shown in Fig.…”

Temperature and chemical composition of droplets by optical measurement techniques: a state-of-the-art review

“…For the purposes of many fundamental studies, it is of interest to characterize phenomena which occur at the droplet scale. Some of these studies deal with motionless droplets which can be suspended on a wire (Saharin et al 2012), levitated by means of optical tweezers (Ashkin 1970), ultrasonic acoustic fields (Tuckermann et al 2002) or electrodynamic quadrupoles (Heinisch et al 2009). Single moving droplets and streams of monodisperse droplets formed through a continuous jet breakup are also frequently used for studying the elementary properties of droplets (König et al 1986).…”